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821.
范召应 《湖南环境生物职业技术学院学报》2012,(2):27-29
目的:报道1例青春期会阴部软纤维瘤的临床特点及病理特点.方法:通过1例16岁女性软纤维瘤患者,结合文献报道,明确软纤维瘤的特点及治疗方法.结果:患者,女,16岁,发现会阴部肿物4年.专科体查:右侧大阴唇外下方可及一带蒂赘生物,约8.0×6.2×4.4 cm,蒂部细,直径约0.5 cm.病理诊断:软纤维瘤.结论:青春期会阴部软纤维瘤少见,它是一种良性肿瘤,应尽快手术治疗.图2,参8. 相似文献
822.
我国现行职业病诊断鉴定法律制度存在较大缺陷,使得受害劳动者维权乏力,笔者在分析探讨职业病诊断鉴定制度所存相关问题的基础上,有针对性地提出改革完善的相应建议,同时对新出台的《职业病防治法修正案(草案)》的有关修订内容做出评议。 相似文献
823.
Henrik Brumm Sue Anne Zollinger Peter J. B. Slater 《Behavioral ecology and sociobiology》2009,63(9):1387-1395
Several recent studies have tested the hypothesis that song quality in adult birds may reflect early developmental conditions,
specifically nutritional stress during the nestling period. Whilst all of these earlier studies found apparent links between
early nutritional stress and song quality, their results disagree as to which aspects of song learning or production were
affected. In this study, we attempted to reconcile these apparently inconsistent results. Our study also provides the first
assessment of song amplitude in relation to early developmental stress and as a potential cue to male quality. We used an
experimental manipulation in which the seeds on which the birds were reared were mixed with husks, making them more difficult
for the parents to obtain. Compared with controls, such chicks were lighter at fledging; they were thereafter placed on a
normal diet and had caught up by 100 days. We show that nutritional stress during the first 30 days of life reduced the birds’
accuracy of song syntax learning, resulting in poorer copies of tutor songs. Our experimental manipulations did not lead to
significant changes in song amplitude, song duration or repertoire size. Thus, individual differences observed in song performance
features probably reflect differences in current condition or motivation rather than past condition. 相似文献
824.
Floods are the most common type of natural disaster in both developed and developing countries and have led to extensive morbidity and mortality throughout the world. Worldwide, over the past 30 years, flooding has claimed the lives of more than 200,000 people and affected more than 2.8 billion others. The impact of flooding on health varies among populations and depends primarily on vulnerability and the kind of event experienced. It severely disrupts livelihoods and has a significant impact on the health of pregnant women and children. In addition, it may exacerbate a range of negative psychological and physiological child and reproductive health outcomes. Awareness‐raising, education, and the issuing of warnings appear to be key initiatives to mitigate or prevent flood morbidity and mortality, especially among people living in low‐ and middle‐income countries. Agencies responding to emergencies also need to be more cognisant of the dangers, specifically those engaged in healthcare, nutrition, and water safety programmes. 相似文献
825.
826.
Network theory is commonly used to reveal social interactions and the organisation of interconnected nodes—but has not yet been applied to animal invasions. Non-native species invasions are now considered one of the foremost threats to natural ecosystems and biodiversity. This is the first attempt to assess social network properties within a freshwater fish assemblage invaded by a non-native fish species. We show that invasive sunbleak Leucaspius delineatus is socially more strongly interconnected with native species than the native species with each other. The social networks also reveal characteristics of a ‘small world’ such as low clustering coefficients C and short path lengths L. The findings may indicate potential traits of successful invaders and the implication for the spread of pathogens between individuals within a group of animals that contain a non-native invasive species. The success of establishment and subsequent invasion may be highlighted not only by the capacity of the new species to adapt to the new environment, but also in its capacity to penetrate the social circle of the native community. 相似文献
827.
钢桥因具有跨径大、承载能力强、施工工期短等特点,被世界各国广泛采用,但在使用过程中,由于重载甚至超载车辆的反复作用、自然灾害的侵袭及交通事故等人为因素的作用,经常造成桥梁损伤和局部破坏,导致桥梁承载能力和耐久性的降低,甚至影响到运营的安全。本文建立了钢拱桥的健康检测和安全评价方法,采用防腐涂层厚度测定、结合强度测定、无损探伤和动静载荷试验等手段对紫下大桥健康状况进行了检测,采用不确定层次分析法对大桥进行了安全评价,提出了处理意见和措施,为既有钢拱桥的健康检测、评价和维护积累了有益的资料。 相似文献
828.
Urban planning involves compromise between the diverse and often contradictory issues supported by the different stakeholders. The literature generally agrees on the need to broaden the participation base to overcome this difficulty. However, participation should not be limited to problem solving, but should also take place in the problem setting phase. This paper proposes a participatory diagnosis process for structuring the problem setting phase. We describe an experiment in a participatory diagnosis conducted with the residents of a Geneva neighborhood. The experiment began by identifying the residents' concerns, which were then reformulated under broader issues. Some 20 spatial indicators were built using GIS tools, and were then applied in a second phase of resident consultations to assess the relative importance of each issue. The ensuing priority issues formed the core of the diagnosis. The approach emphasized comparison between the daily experiences of residents and so-called official information (i.e. census tract, traffic measurement, and so on). The residents were therefore involved in a learning process that allowed them to consolidate or modify their opinions. The process led to the emergence of a clearly defined collective awareness that supplanted individual aspirations. 相似文献
829.
为解决分接开关故障诊断以主观经验、缺乏系统化流程以及诊断结果与分接开关实际发生故障存在偏差等问题,依据当前分接开关主要故障分类,提出基于模糊Petri网的有载分接开关故障诊断模型,并结合分接开关典型故障案例,验证模型有效性。研究结果表明:基于模糊Petri网的分接开关故障诊断模型能够有效处理故障概率中不确定性因素,具有容错性好、运行效率高等优势,研究结果可为提高分接开关故障诊断的准确性、保障电力系统安全稳定运行提供参考。 相似文献
830.
面向复杂设备的分布式故障诊断研究 总被引:11,自引:0,他引:11
基于复杂系统的设备故障诊断的要求 ,按故障信息流动的方向将诊断过程分为实时监测层、故障诊断层及综合决策层 ,并建造一种分布式多级黑板诊断结构模型。根据不同诊断层次的特点 ,赋予其不同的诊断方法。在实时监测层中各实时监测单元采用神经网络和知识基模块的混合结构完成该层任务 ;故障诊断层则基于广义知识表达模型 ,建立三库结构 ,即静态实例库、动态实例库和规则库 ,整个推理过程基于三级推理机制 ;综合决策层为一智能型的辅助决策支持系统 ,提供对整个系统生产与设备运行状态的综合诊断与决策。 相似文献